1. Field of the Invention
This invention relates to steps and in particular to a tread plate for a step which has improved safety and wear characteristics.
2. Prior Art
Previously, protective tread plates for stair or step treads have been known, especially for railroad cars. They have consisted of single piece, ridged metallic plates. However, the ridges often filled up with dirt or debris thereby reducing or eliminating the gripping or frictional effect for which the ridges were provided. Furthermore, use made the top surface smooth so that, in wet weather especially, the foothold was rendered increasingly slippery.
Other previous tread plates are known which were made of a single piece of metal on which a very thin sheet of abrasive, gritty material was placed. Of course, within a short time the sheet wore out and required replacement. In both types of prior art plates the visibility of the plates was less than satisfactory; passengers, especially at night, found it difficult to see the edge of each step.
It is among the objects of the present invention to provide an improved tread plate which enhances the foothold of users and is more durable in this respect and which promotes safety by making the steps and their edges more visible.